Project Id: 2010OK181B
Title: A Fluvial Geomorphic and Sediment Transport Study of the Little River Upstream of Lake Thunderbird Using an Acoustic Doppler Current Profiler (ADCP)
Project Type: Research
Start Date: 3/01/2010
End Date: 2/28/2011
Congressional District: 4
Focus Categories: Sediments, Geomorphological Processes, Water Quality
Keywords: sediment transport, bed load, ADCP
Principal Investigators: Kolar, Randall L.; Julian, Jason P. (University of Oklahoma); Nairn, Robert; Vieux, Baxter
Federal Funds: $ 25,000
Non-Federal Matching Funds: $ 58,567
Abstract: Sediment transport has a profound impact on lakes and impoundments, affecting not only the lifespan of the water body due to lost capacity, but also the water quality, as many nutrients and contaminants (e.g., metals) are bound to the solid particles. Yet, given its importance, it is one of the more poorly quantified water quality variables, primarily due to the difficulty in obtaining accurate estimates of sediment transport, both in the water column and tributary bed loads. Hence, it is not surprising that sediment yield appears as one of the primary focus areas for this year's OWRRI research grant competition. The proposed research project aims to fill these knowledge gaps by establishing an accurate and reliable measurement protocol for determining sediment yield utilizing Acoustic Doppler Current Profiler (ADCP) technology; Lake Thunderbird will serve as a test bed for the methodology.

Lake Thunderbird supplies drinking water to the municipalities of Norman, Midwest City, and Del City. The lake is designated in the Oklahoma Water Quality Standards as a sensitive public and private water supply with a nutrient limited watershed. Almost 12% of the lake's capacity has been lost to sedimentation in a mere 36 years (1965-2001), but little is known about the sediment transport in the tributaries of the lake, including the Little River. The Little River's proximity to the OU campus, and the fact that it is representative of many streams in central Oklahoma, makes it the ideal location for testing the proposed methodology.

The ADCP will be used to measure stream discharge and both suspended and bed load sediment transport rates over a large range of discharges. The discharge, suspended and bed load sediment transport rates measured with the ADCP will be used to develop sediment rating curves for the river. These relationships will then be used in conjunction with a frequency-duration curve, generated using hydrodynamic computer models (since gauge data is unavailable), to estimate annual and long-term sediment loading rates delivered to the lake from the Little River watershed. The ADCP will also be used in conjunction with an RTK GPS receiver to develop the elevation profile of the river bed from the lake to the headwaters.

The proposed study is being coordinated with, and will supplement, on-going work being conducted in the watershed by the Oklahoma Department of Environmental Quality (ODEQ) and the Oklahoma Conservation Commission (OCC).

Many streams in Oklahoma are incising and widening, resulting in much damage to property, roads and bridges. Knowing how much channel incision and widening is expected to occur would be beneficial to society, in general, and the State of Oklahoma, in particular. The use of an ADCP to estimate these sediment loads is a departure from traditional hand-sampling techniques. Thus, the methods being investigated in the proposed study, if proven effective, may then be applied to streams and rivers throughout the state in order to economically develop sediment loading rates for all of Oklahoma's reservoirs. In fact, the Grand River Dam Authority (GRDA) has already expressed an interest in applying the proposed methodology to similar studies in the Grand Lake watershed.